Porous metal flow master

Abstract

A flow master for testing a leak test head includes a housing having an upper body portion and a lower body portion, the housing defining a passageway therethrough, the housing further defining an internal volume substantially equal to a fuel volume of a fuel injector to be tested; and a porous metal flow restrictor disposed in the passageway. A method of testing a leak test head includes providing a flow master; measuring a flow rate of the flow master from a known standard; connecting the flow master to the leak test head; pressurizing the leak test head; measuring a flow rate through the flow master using the leak test head; and comparing the flow rate measured by the leak test head to the flow rate measured by the known standard to determine if the leak test head is accurate.

What is claimed is:  
     
       1. A device for testing a leak test head, comprising: 
       a housing having an upper body portion and a lower body portion, the housing defining a passageway therethrough, the housing further defining a predetermined internal volume related to a fuel volume of a fuel injector to be tested; and  
       a porous metal flow restrictor disposed in the passageway proximate one of the upper and lower body portions, the housing and the porous metal flow restrictor adapted to test a leak test head.  
     
     
       2. The flow master of  claim 1  wherein the internal volume is defined in the upper body portion. 
     
     
       3. The flow master of  claim 1  further comprising a porous metal sintered filter disposed in the upper body portion of the housing. 
     
     
       4. The flow master of  claim 1  wherein the upper and lower body portions are threadably engaged. 
     
     
       5. The flow master of  claim 4  wherein the upper and lower body portions are sealed together with an O-ring. 
     
     
       6. The flow master of  claim 1  wherein the upper body portion includes a retainer and an O-ring for sealing the flow master to the leak test head. 
     
     
       7. The flow master of  claim 1  further comprising a pair of O-rings disposed at opposite ends of the porous metal flow restrictor for sealing the porous metal flow restrictor in the passageway. 
     
     
       8. The flow master of  claim 1  further comprising a hose barb connected to the lower body portion. 
     
     
       9. The flow master of  claim 8  wherein the hose barb is threadably engaged to the lower body portion. 
     
     
       10. The flow master of  claim 1  wherein the housing is made of stainless steel. 
     
     
       11. The flow master of  claim 1  wherein the upper and lower body portions include wrench flats. 
     
     
       12. The flow master of  claim 1  wherein the porous metal flow restrictor is calibrated to a flow rate of one of 0.1, 0.2, and 0.5 cubic centimeters per minute. 
     
     
       13. A method of testing a leak test head, comprising: 
       providing a device with a housing, the housing having a passageway between an upper body portion and a lower body portion, and a porous metal flow restrictor disposed in the passageway;  
       measuring a flow rate of the device from a predetermined value;  
       connecting the device to the leak test head;  
       pressurizing the leak test head;  
       measuring a flow rate through the device using the leak test head; and  
       comparing the flow rate measured by the leak test head to the flow rate measured by the predetermined value to determine if the leak test head is accurate.  
     
     
       14. The method of  claim 13  wherein the housing further defining a predetermined internal volume related to a fuel volume of a fuel injector to be tested. 
     
     
       15. The method of  claim 14  wherein the internal volume is defined in the upper body portion. 
     
     
       16. The method of  claim 14  wherein the device further comprises a porous metal sintered filter disposed in the upper body portion of the housing. 
     
     
       17. The method of  claim 14  wherein the upper and lower body portions are threadably engaged. 
     
     
       18. The method of  claim 17  wherein the upper and lower body portions are sealed together with an O-ring. 
     
     
       19. The method of  claim 18  wherein the upper body portion includes a retainer and an O-ring for sealing the device to the leak test head. 
     
     
       20. The method of  claim 19  wherein the device further comprises a pair of O-rings disposed at opposite ends of the porous metal flow restrictor for sealing the porous metal flow restrictor in the passageway. 
     
     
       21. A flow master for pressure testing a test unit, the flow master comprising: 
       an upper body portion extending between a first upper body end and a second upper body end along a longitudinal axis, the upper body portion including:  
       an opening proximate the first upper body end, the first upper body end having a retainer and an O-ring adapted to be inserted into the test unit;  
       a first passageway extending between the first upper body end and second upper body end, the first passageway defining a fluid volume generally equal to a fuel volume of a fuel injector;  
       a first threaded portion proximate the second upper body end; and  
       a lower body portion end extending between a first lower body end and a second lower body end along the longitudinal axis, the lower body portion including:  
       a second threaded portion proximate the first lower body end, the second threaded portion being coupled to the first threaded portion;  
       a second passageway extending between the first lower body end and the second lower body end, the second passageway aligned with the first passageway along the longitudinal axis;  
       a porous metal flow restrictor located in the second passageway; and  
       a barbed fitting proximate the second lower end.  
     
     
       22. The flow master of  claim 21 , wherein the porous metal flow restrictor including a porous metal flow restrictor calibrated to a flow rate of at least one of 0.1, 0.2 or 0.5 cubic centimeter per minute.